Sorry, I missed the last part of the OP and get it now.
I still wouldn't do this myself but can understand the benefit of it in theory assuming nothing changes when it goes live. On paper, it seems like a sound risk/investment if you've got the time now. More so if you already have all the mats ready to go and ready for live.
Though, in theory, (particularly if you need to grind out lots of mats to do this now and finish it post launch) there's an argument that says all the time spent completing these single g5 rolls may just save you the time it takes to click through g1 to g5, but cost you more time getting all the mats you need.
It's entirely possible the time spent now hunting g5 mats would have netted you more than enough lower grade mats to convert or use had you waited to do it post launch, given the 100 limit in the new build and the trader. You'll still need three or so g5 rolls for every module, one of which you'll have wasted by doing it now (so 4 or so). It's likely you'll need to get plenty of g5 mats post launch, which will provide you plenty of lower grade stuff. Doing that farmathon now means you'll pass up on a lot of trash mats that might give you an edge post launch. This will be particularly the case if the trader enables us to skip RNG time with converting to g4s and g5s, or trading those useless g5s down to useful g4s or g3s.
Worst case, you spend more time farming now than you would need to post launch, for the same result.
I'd rather just do it when it goes live based on what I need but that's just me and my personal requirements. At the very least, I'd wait until beta launched to get an idea how much time would be saved. I'm not convinced it's as simple as the number of mats you need in either build. There's going to be a reason Sandro seems confident it'll be easier overall and I think it's because mats collection will be laterally faster than now.