I recently bought a used LP50.... I shoot Bullseye but more and more I'm getting drawn into 10m AP!
In any case, it is certainly not the holy grail of bullseye training devices. I do not have the 1911 grip or heavy trigger; I got the LP50 for that *option* but I am not sure I will ever use it (possibly interested though if anybody selling their accessories...). In any case, the compensator eliminates any significant muzzle rise. So yes there is some benefit to sustained fire training, but I don't think any benefit in terms of recoil management, which seems to be what you want. IMHO, the challenge of sustained fire with a .45 is getting on that trigger while you still have no sight picture...the LP50 is not for that...unless you throw your arm up in the air or have a training partner slap your arm up from under after each shot ;-) Not to digress, but I am of relatively slight build and my sustained fire benefited greatly from 2 things primarily:
1. Taking grip strength training very seriously (google "captains of crush" or maybe crunch, I forget...but they have some great grip building tools)
2. Leaning forward significantly.
Anyway, what I have played with
There are some very excellent and accurate airsoft 1911 out there. The ones with gas blow back have about the same recoil force as SV .22 ammo. I have cheapo($100) that holds the 10 ring and 15 yards, or a quarter at 20 feet when I practice in the garage. Mine is co2 powered but it can also take propane from a camping cylinder. Lots of fun, and some of them you can even put your own 1911 grips on if I'm not mistaken. Tokyo Mauri is considered the most reliable and most customizable brand, also the most expensive. These are really high quality replicas, you can come very close to the weight and balance of your .45, the trigger...we'll that's tough...but if recoil management is what you want then this will help a little to build confidence...it ain't no .45!
If you can find one...crossman used to make a 1911 conversion kit, a 1911 upper that took a co2 capsule and shot .177 pellets, so you practice with your own 1911 trigger. It was the crossman/blaser 455. It only takes one pellet at a time, again no holy grail.
Also a S&W 78G when I thought I wanted a M41.