Choice of One

So if in the price was not a barrier, for BullsEye, which is the least problematic and forgiving?  Pardini, Matchgun or Walther?  Consider, servicing, parts, repair and ammunition.

If you watch the issf pistol matches on youtube you would be hard pressed to find anything other than pardini.

For Bullseye a 1911 Conversión in a dedicated lower for maintenance and availability of parts.

If considering one of the "current" ISSF guns, In order of preference I would take Pardini over Matchgun, have seen Matchguns have too many issues on the line (not necessarily the guns fault). I have hardly seen any of the newer walthers on the line, so I can not comment on them. AW93 is another option to consider, I have seen many have good success with them.

My first choice for a 22 for bullseye is a Nelson 1911 conversion (Marvels are good choice too). As stated above the majority of the parts are shared with the 1911 platform. 

For what it is worth, I have an extensive selection of match 22 options (208, 41, Ruger, 1911 conversions, ect.). I have also shot Pardini's, Matchguns, and AW93. If good effort is put forth all options mentioned will not hold you back.

I have and use a MG2, does some great things at matches and the only issues I have had was due to: bad lots of ammo, a loose grip, and the round elevation ball popped out of the rear sight.  (Same bad lots of ammo gave me problems with my XESSE as well.) With that said I am going back to using a XESSE for Bullseye with 1911 grip conversion.  Main point is to match my .45, when heavily using a European grip angle and going back to a more vertical grip like a 1911 it takes some getting used to rolling your wrist to bring the sights back up.  Easier transition if the grip angle semi matches.  I never shot a 208 or Pardini, but in the competition circle for support and parts or even borrowing magazines, I would say Pardini is paramount.  (I am pretty interested in the GSP500 though, if they are ever imported and priced decently.).

Hammer6048,

Pardini, hands down! 

The simplest gun to clean, by far. Very accurrate. Very reliable (especially with Eley Bullseye Pistol X - specified by Pardini USA). Low'ish maintenance cost for the 22 (just replace the recoil spring every 20,000 rounds or so - buy the spares kit offered by Pardini USA, just in case). Best customer support. Their van is usually at Canton and Perry every year as well as many of the International matches. I own several - never had a serious failure during any match since I got the first Pardini about 5 years ago. Very few alibi's, almost always due to a dud (that usually went bang second time). The trigger can be adjusted, but I find that quite tricky to get perfect, but maybe I'm just a klutz! I prefer the Rink "upright" grips, somewhat closer to the 1911 angle.

And, to put my comments into perspective:- I owned and sold on an MG2. I owned and sold on a Walther GSP (admittedly an older model and at the very start of my Bullseye endeavor).  A Britarms 2000, briefly. Several Marvels on dedicated lowers. Two very nice Ruger 22/45's. Recently acquired 208S with 1911 grip (an "itch I just had to scratch").

My first and best Marvel was bought in order to train with a 1911 gun - hoping to improve my 45 scores. Good gun, good idea, shot it a lot and it probably helped me somewhat. But I have never been able to beat or even match my Pardini scores. And it has not been perfectly reliable.

Pardini, hands down!

YMMV

What is your budget? 

Under 1000 then Browning or Ruger, maybe Conversion
1000 to 2000 then Marvel on a dedicated lower, GSP post 1984, Xesse SF , M41
+2000 AW93, GSP Expert, Pardini , 208s 

ISSF Pardini seems to win everything over the last decade +

Matchgun MG2.   The only issues I've seen are from people using crap ammo in their guns.  I've been using an MG2 for almost 2 years now and I've never had an alibi with it.

When Benning hosted a few ISSF matches Adam said 95% of the shooters used Pardini! Even the Russian shooters were using Pardini! But AMU bullseye shooters were using Hammerli 208 though modified to have 1911 grips and grip angle. They were also experimenting with Marvel/Nelson conversions on dedicated frames. Though Adam retired he does have a 208 modified and another as is. However he has 2 Nelsons that he's working on.
 Advantage of the conversions is they put "One Gun" in the hand, few of the top civilian shooters are using the Conversion for that reason.
 If I were to recommend a gun to start with it would be the conversion!

Is there a reason High Standard is not in the mix??

Thanks in advance
Jim