first off I am fairly new to the forum so hello all, and I just wanted to know what kind of engine swaps you guys have done to your Infiniti.

My engine blew on my 06 m35x at 250k miles and just put a new vq35de in instead of buying a new car since the transmission, brakes, suspension, etc all still in great condition since all I used it for was commuting from work/school and never ran it hard. The new engine has about 120k on it now but I am wondering if instead of swapping it for the same engine I could have swapped it for the m45 or m56 engine for more power even though it would have been a bit more money. just curious if any of you have either had the same question or had done a swap like this.

There have definitely been some M35->M45 swaps but that's about it.

Its not like the old days. Swapping in a different more powerful engines needs a lot more work than in decades past to make the varios electronics module "talk to" one another properly.
Also sometimes there are challenges in making the new engine mate ot the old transmission. ( though boith engines used the same tranny model , except the one in the V8 cars got an upgraded clutch pack, likely some programming differneces as well)

Swapping in a replacement engine of the exact some kind, say VQ35de to VQ35de as in your example is so much easier.
Can it be done to go to V8, but not likely for those who are on tight budgets like in decades past.

Some popular swaps come with kits though.
Like XTerra or Fontier swapping the V6 out for a Nissan V8, thats become more common and may evne be moderatly economical if the base engine somehow got broken.

Yeah, you can swap anything if you have money. You could probably put a Ferrari V8 in if you had an unlimited bank account lol.

PS: sorry for my typos