Sure, Saab convertible roofs are heavy canvas so they last pretty well. The main thing you need to do is keep them clean so dirt doesn't stiffen the fabric and cause pulls or brittle areas. As for cleaning; use regular car soap and a sponge, or a soft brush on tough areas if needed. I found a nice long handled "trim" brush that has very soft bristles; and it works great on the top when I need to scrub dirty areas.
Every year to two you should treat it to maintain the water resistance and protect it from fading or breakdown from UV; and there are two main products I know of that will do this really well. Either works great, pretty much up to you which to use.
I just did the full Renovo treatment; re-painting and waterproofing, and it was OK but not brilliant. The paint/dye just about managed to cover up some marks that I made by putting the top down when it was still wet (naughty boy:nono; ), and the waterproofer isn't 100% effective, as the top still gets soaked in places.
Previously, I just used fabric waterproofer in an aerosol (the kind you use on jackets, etc.), which does a better job of keeping the water off and is a lot cheaper than the Renovo. It only lasts 2-3 months, tho', and you use most of a tin each time...