Thinking about buying a GRiSO, but which one?

I've never ridden a GRiSO, but I owned a V50 and a Le Mans 2 in the 80's and have another Le Mans 2 in my garage at the moment which I've rebuilt virtually from the ground up. It shares the garage with a Gen 1 Aprilia Tuono and a Honda CB1300.
I love the looks of the GRiSO and am seriously thinking of buying one, funded by the sale of the Le Mans.
Questions I need to ask as follows:
Is there a big difference between the 1100 2v and 1200 4v versions?
Is there any quick way to confirm that a 4v has been rollerised, or would I need to ask that the valve covers are removed to confirm?
I've seen that oem fuelling can be a problem...in what way? Can the ECU be chipped (I've re chipped my Aprilia) or can it only be flashed?
If flashing is the way to go, can a good map be downloaded from a 3rd party and easily installed?
Thx for any replies, I'm sure I'll have more questions in time.

1. No very big difference between the 2V and 4V but, yes, the 4V is faster and more powerful while the 2V has a more raw character. The 4V engine is perhaps more refined but does seem to be more finicky, or at least does seem to result in more requests for technical help on the Ghetto (but of course has been sold more as well).
2. There is an 'official' cut-off VIN (mentioned somewhere in a post on this forum), but there are exceptions reported so removing the valve covers is the only sure way to find out (and takes 5 minutes).
3. OEM fuelling is fine but a Beetle map transforms it to GREAT.  You can contact Beetle via this forum, or on his website GRiSO.org.  Changing maps is not difficult. A tutorial can be found on Beetle's website, or on this forum ([You must be registered and logged in to see this link.]).

There are several highly skilled technical gurus active on this forum (i.e. not me) who can give you all the assistance and guidance you need. Do a lot of searches and feel free to ask.

GuzziRider850 wrote:

Is there any quick way to confirm that a 4v has been rollerised, or would I need to ask that the valve covers are removed to confirm?

It was the early 4V per cylinder - or 8V total - motors that were provided with flat tappets. Guzzi changed to Rollers on what they call the 1200 8V motor during the 2012 model year. So the quickest way to be sure you get a rollerized motor is to buy a 2013 - 2017 model year bike.

If you find an earlier model, you can actually eyball it with the valve cover off, which does take a few minutes.

I don't know that I'd be able to part with a LM II that I had that much sweat equity into....

Welcome to the Ghetto.

If you look at a 8V before 13', look under cover, if owner says no, I would move on!! You can see the rollers & fork. I helped my friend w/1100, 90rwhp. He had heads flowed, cam, all the 2V hotrod stuff.
Pete here calls those "grenades" but it's OK as long as you stay in the safe zone.