Been loading 10mm, and everything else, for decades. My goto 10mm powder has been Blue Dot and it works well but I thought I would try Longshot since that is what I load in 20ga and I have a bunch of it (and ot gets me a few more FPS according to the book). I loaded 5 groups of five rounds starting at 8.3gr going up to the "book max" of 9.5gr in .3gr increments. I am using Hodgdon data for the 180gr Sierra bullet but I am actually using Zero 180gr JHPs, bullets I have been using for a very long time and they perform well and look like exact copies of the Hornady XTP without the cannelure. All these were tested out of a new XDm-10 4.5 that I just picked up. All charges were thrown and measured with a Pact dispenser and scale. Bullets were seated to 1.260 and lightly crimped. My results were very surprising. Primers were CCI LP and brass, while consistent within the 5 round groups was either PPU, Hornady or A USA. All rounds showed primer flow (even the blue dot loads) but none of the primers were what I would consider flat. According to Hodgdon's load data 9.5grs out of a 5" barrel maxes out at 1287FPS. I hit that with 8.9grs out of a 4.5 inch barrel. The firing pin hole in the XDm slide is quite large so the primer flow is not as concerning as it would be on say a GLOCK but it was significant. Anyone else using Longshot and seeing some issue towards the top of the "book" loads? For comparison I put the Blue Dot velocities below the Longshot data. In the pic the case marked with red is the top and silver is the bottom charge.

Longshot
Charge.       Ave FPS.       SD
8.3              1212.           2.91
8.6              1259            3.07
8.9              1288            8.69
9.2              1315            8.27
9.5              1353            13.11

Blue Dot
Charge.       Ave FPS.       SD
9.6              1099.           14.92
9.9              1134            15.60
10.2            1163            22.63
10.5            1190            9.23
10.7            1213            9.54

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Late to the party but thought I would weight in....
I started reloading in the 90s with a Lee Turret Press, added 2 Load Masters, then 2 Dillon 650s, a Dillon 1050, a Lee Pro 1000, a Lee Breech Lock Challenger and some shotgun presses. Today I have one Dillon 650, one 1050, and the Lee Breech Lock Challenger (I just sold the original turret press about a year ago). Sorry I cannot give you any feedback on the Hornady but that is one of the few presses I have never used. Here are quick thoughts on all I have used:

Lee Turret press: great simple press if you are loading a few hundred rounds at a time. Simple to use. I added another Turret press with the auto index feature later but I found the plastic bushing for the Auto-Index to be a weakness and preferred rotating the tool head by hand. Great press and inexpensive for setting up tons of calibers in their own tool head and quickly switching back and forth without having to monkey with dies.

Lee Load Master: probably the best press for the money! Same tool head design so I had multiple tool heads that allowed a quick change between calibers. The Achilles heel of this press is the primer feed system but since you can by 3 of these for the price of a Dillon 650 do the math. If you buy one of these the coveted secret is that you will need two sizing dies. One goes in the normal sizing/depriming station and the second one, with the deprimer removed, goes in station 2 to hold the case securely while inserting the primer. If you do this you rarely have a problem with the Loadmaster.

Dillon 650 is a great all-round press for those who are loading lots of ammo with no military brass and Dillon support is good AS LONG AS YOU DO NOT ALSO ADD A 1050 (more about this later). Dillon is expensive up front and expensive to add more calibers to. In fact, you can almost buy a Loadmaster in a new caliber for what the additional parts cost to change calibers in a 650 (you could definitely buy a Pro1000). The 650 primer system is the best out there period, dependable and safe.

Dillon 1050 - great press if you are loading lots of ammo that includes military brass. There is a swager built in that removes the crimp on military brass primer pockets. Very very expensive to get into and crazy expensive to have multiple tool heads and calibers. Just a tool head with no dies or conversion kit is almost $200. ALSO Dillon considers this a "commercial" machine and warranty is only a year. Furthermore if you have a 650 and a 1050 and call for service you get the 3rd degree so they are comfortable that you are not trying to get free support for your 1050. Primer system is temperamental and a primer that fails to seat creates a domino effect, a real PITA!

Lee Pro 1000 - not as robust as the Loadmaster, very fragile primer system, issues with the powder measure that comes standard, and not enough die positions. But they are inexpensive. There is an upgraded powder measure that eases the pain there but I consider 5 holes in a tool heat the minimum.

Lee Breech Lock Challenger - love this press. Single stage but I have a 2nd or 3rd set of dies for every caliber I load on the progressive presses with a breech lock on it so I can load every caliber single stage. This is what I use for all my rifle except 223. I use the 1050 for 223 unless I want match 223 then I use this press. It is amazing how much more judicious I am pulling the trigger when I have to load the ammo on a single stage press!

Couple more notes...

1st - I DO NOT recommend a Dillon 550. A press like the Loadmaster or Pro-1000, while not as robust or heavy duty, auto-indexes which greatly reduces the chance of a double charge. I have seen a half dozen different folks blow mags out of the bottom of their Glocks and when asked what press they use I always get "a 550". Especially if you are new to reloading, get a press that auto-indexes so when the kids come up to say hi or the phone rings and you get side tracked you almost completely eliminate the ability to double charge a case.

2nd - No matter what press you have you have to pay attention, go slow initially and then do not get complacent. If something does not feel right is probably isn't so stop and make sure rather than applying more pressure.

3rd and last - know how your press works and keep it clean!!! No matter which press you buy you will end up taking it apart to clean it or to diagnose a problem. If you understand how it works you will be light-year ahead in making safe, quality ammo!

4th - Ok I lied, this is the last one.... A Lee Factory Crimp Die is a must have for every caliber.