Assuming that the base for all ‘extenders’ is roughly the same— some manner of spring loaded device encircling the root and providing for an appliance ‘head’ that can be attached toward the distal end of the penis, thus maintaining an ‘extended’ or stretched state, the question becomes one of which ‘head’ works best for the individual reposting.
In my PE travels I’ve tried a number of appliance ‘heads’ that I’ve switched out on my Andro-Penis base— I very quickly found the noose-type head worse than useless.
I believe that it was monkeybar who produced the old style silicone cushioned C-clamp head that I first swapped out— while far superior to the noose [at least it stayed put] I found it too to be very uncomfy for me— and as I’ve said here many times, I’m a pussy when it comes to dicky pain.
I’ve also used a Vac style head— although not with the Andro base [rather in a root loop configuration] and found that while very comfy [was able to wear 600+ hours in less than 60 days] I never really got the sense that it was grabbing onto the underlying meat but rather simply using the vacuum to pull the penis by the skin- probably not a bad idea if one simply want to maintain an semi-stretched state.
But again, I wasn’t using it with my springloaded Andro [JES style] base— so take that into consideration in reading this.
What I’ve had the most success with is an aftermarket PeniMaster style strap head I found on eBay that I swapped onto the Andro base— it seems to maintain a fair balance between general comfort — it still needs ‘numbness’ management, but no localized pain/ discomfort like the noose or clamp- and ‘bite’ [unlike the Vac products I get the sense that the strap is actually gripping the meatus and pulling it rather than just kinda sorta ‘holding’ it in a superficially extended state.
Hope this helps.