Other than weight, are there any major issues. It will be suppressed and have a Burris FFIII

My issues:
-Took me forever to decide on not getting buckmark (primarily because of extra inch barrel length) Not sure if some rounds would go supersonic.
-Part of me would like the bottom rail for a lite with the standard 22/45
-weight difference between the two as far as shooting, etc..
-accuracy differences?

Looking for you guys that have both or have used both.
I also am wanting the black fluted version in the lite, have any changes improvements been made to the lites since that version came out a couple years ago?

Thanks so much in advance.

I've owned both guns.  Get the lite version if your shooting suppressed.  A must have is the bushing from tandemkross

http://www.tandemkross.com/Steel-Hammer-Bushing-for-Mark-III-and-2245-Pistols_p_9.html

Thank me later.

Thanks for the help! Ill definitely get that part!

Gander Mountain has short barrel Buckmarks at a good price, unfortunately not threaded.

As far as I know, the biggest difference is in the weight.  I handled both in the gun shop, and settled on the original gold Lite, even though I didn't love the color scheme. Accuracy was good, although I'm not that great of a shot and typically use bulk ammo for my pistol.  I traded it in for the black fluted model a year or two ago and couldn't be happier, except if it would clean itself.  Taking down these Rugers can be a pain!

I second the motion to get the Lite, especially considering you'll be running suppressed and the weight savings should help the balance (in my opinion/experience).  I also second the Tandemkross bushing, and suggest the Kane Wolf bolt catch (allows slingshotting the bolt), and a Volquartsen sear. Some people recommend removing the loaded chamber indicator - I've run both ways and didn't notice any difference, although I prefer the cleaner lines of the elimination plate, as long as it stays in place.

Lite. Had a bull barrel before, sold it. Gave the 22/45 another chance when the gold Lite was released. Much happier.

I have one of each.

22/45 Mk II, very accurate and I appreciate the heft of the full bull barrel, the all black sights are irritating at times.  Don't know if the standard sights have changed in the last 10 years or not.  The trigger has worn in to the point of being rather crisp and very consistent, a much appreciated thing in my eyes.

22/45 Lite, have put probably 5-800 rounds through it.  I find the center of balance to be MUCH further to the rear,  comparitavely speaking.  Hanging a can off the barrel would probably compensate for that.  The trigger seems a little grittier on this one.  Realistically that is probably the difference in several thousand rounds through the Mk II.  

IIRC mags are interchangeable one way, but not the other.  Don't remember and am not positive.  Someone will be along to confirm or correct.

If forced to choose I would keep the 22/45 and ditch the Lite.

HTH

To follow up on rbblrwsr's magazine note - you can use mk iii magazines in mk ii guns, but not the other way around by default. If you add the magazine disconnect safety bushing eliminator from Tandemkross or other sources, you can use Mark II magazines in newer guns. It also allows mags to drop free - it's easily the best $10 you'll spend.

Also,  the comment about sights reminds me that they're easy to change. I personally like the Williams Fire Sights.

I had to make this same choice recently.

I went with the 22/45 lite and am very happy with it. With a can it really balances well.

I had a Mark III Hunter (stainless with 6"+ barrel). It was entirely nice in a different way.