Unless you are gonna do some other mods, the drop in's are the way to go. They will be easy on the top end and you can run the stock tensioner if you like.
Aftermarket cams are in the .370-.380 lift range which will require higher compression to really shine.
I have a set of drop-ins to install in the spring. I am not worried about losing any midrange, the B12 stock has a powerband like a big twin with peak power below 9000rpm. The GSXR cams will turn it into a real in-line 4 pushing the powerband up to 10,500rpm. This is not a 750, it is still gonna have decent midrange, even with the GSXR cams.
Good Luck, Ed.
2005 GSF1200SZ
1983 GS750ED