I don't know that 1/5th specifically. I've had 4 or 5 savage's over the years, currently have 2, a flux hp and savage x. The later models are better because the transmission is a bit lower. The older 25/SS on down to the 21 had a high center with the transmission up higher, which made the dog bones wear out the center cups ridiculously fast.
I've only had one 1/5th scale, the baja 5b ss. It was cool to build and to look at, but single speed just wasn't fun for me. I actually shortened mine by 1.5" or so with an aftermarket chassis, that made it a little more fun to bash, but I had too few of places to run something that size. I got it to run in the winter, since it was a normal engine, they are easier to deal with in the cold. Then I realized 2wd is a stupid vehicle to drive in snow. Not sure why I didn't think of that before spending $1000... In total, I probalby drove it 10-15 times over the couple of years I had it. Then I sold it for $600. One of the few RC's I didn't take a total bath on. With the chassis upgrade, arms, crank case air filter, I was probably around $1200 into it. Means it cost me between $50 and $60 for every drive... live and learn.
Something with 1/5th scale is pump gas stinks and the smell lingers. Living in an apartment with an engine that ran pump gas tends to stink up the entire house for a whole week after running it. Also something I didn't think about. Nitro smells for a day or so after running, but fades pretty quick. Also, it's big and heavy, so there will be breakage and parts tend to not be that cheap compared to smaller RC's.
To have a 1/5th scale again, I'd want a 2 speed with slipper (or something to absorb drive train shock on landing) with 4wd and more than 1" of ground clearance. Even then, for where I have to run something that big, i wouldn't run it much.
So, for me personally, I'd stick with 1/8th nitro.