Very nice work!
There was a thread over at TRF 1 on the stability of the mars lander. I think it benefits from a small amount of nose weight, mine has 2 Estes lead discs. Carl from Semroc also said something about the distance between the legs needs to be 13.5 inches (I Think). And the last thing I remember is the legs need a snug fit around the balsa fairings, if they are too loose the legs can pivot and act like control surfaces.
Mine is a clone, It uses some KosRox parts, a few Semroc parts, and a bunch of stock Estes parts. It's built light, not much paint, and stock. I have flown it many times on both B6-2, and C6-3's. It gets about 90-100 ft on a B6-2 with a full chute about 50ft and about 200ft on a C6-3. I have had one flight on a B6-2 that the chute came out, but did not deploy. This resulted in a cracked leg dowel that was easily repaved. I have also flown it in 7mph winds with no problems. It is a tough bird but it does have marginal stability, I would be very wary of any mods, If I remember correctly, and Carl please chime in if I am wrong, even the Semroc upgrade to fiberboard has a slight degradation in stability due to the added mass.
Please post a painted photo!
Oh and when you store it, keep the weight off the legs. Someone here (I don't remember who) suggested using a spent engine inserted partway to hold up the lander. This improves the life of the rubber bands.