I shot production pistol in IHMSA handgun competition wIth a 10" 357 MAG Contender. I later got a Super 14 barrel chambered in 7mm Int Rimmed.As pistols, with heavy recoil they seem to eat my fingers, I much prefer the XP-100. Most of the ones I have, stay in rifle form.
They shot well but as a handgun, they were a bit of a handfull.
I like 221 Remington Fireball. I traded a 30-30 Win 10" barrel for a 22 Hornet barrel and had the latter rechambered for 221 Rem FB. It shoots well but like a said before, then10"Contenders are a bit of a handful.
I got barrel and stock parts to make a 22 Hornet Contender carbine, it is great. Later, I got a Bullberry heavy 22" Remington Fireball barrel with associated Bullberry furniture. It is one of the most accurate rifle in my collection.
I've never fooled with an XP-100. Maybe someday.
All three of my Contender frames are first generation which have seveal adjustments for the triggers. In the early 2000'. I bought an Encore rifle and was disappointed with the trigger on the Encore. I got my Encore trigger adjusted by changing parts but not as convenient as with first generation Contenders.
I love the Contender/Encore concept but am disappointed with where the manufacturer has taken the product.
I'm not sure were the folks bringing aftermarket frames to market have taken the frames, so no comment here from me.