They are completely different profiles, with the TS1-IM being more of traditional blade look and the TS3.5 being more of what one might consider a Super Game Improvement profile. We list the blade lengths and sole widths and hosel lengths in the specs in our catalog and online, so you should be able to compare those and see the multiple images of the heads to see the difference. Both are considered Super Game Improvement designs based on the Maltby Playability Factor, but he TS3.5 will have a slightly higher playability number. You can see all the MPF numbers here:
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The one thing I would say about taking the TS1-IM and strengthening the lofts, which you can do, is that you will reduce the sole angle, or bounce by the same number of degrees. In other words, strengthening the 6 iron from 28.5 to 26.5 will take the bounce down from 4 degrees to 2 degrees. It will also make the iron appear to have a little mor offset.
In my opinion, if the stronger lofts are the priority, then the TS3.5 would give you that, but you would not get the traditional blade profile. It has a wider sole and more offset as well. All that being said, if you like the TS1-IM because of it’s profile, it already has modern stronger lofts for it’s type of iron (compared to traditional blade iron lofts) and you could maybe strengthen by just 1 degree and it not be so noticeable.
Might be worth the investment to try a 7 iron of each and compare. Better to invest in that test, in my opinion, than to guess and ending up investing in an entire set that you end up not liking. I really don’t think you can make a bad choice from a performance standpoint. It comes down to the specs you want and look you want.
Britt Lindsey