Ah, comparable to the BNP and UKIP then, hmmmm.
As in the relationship between the SNP and SnG is comparable to BNP and UKIP? No, that is not the case. I may disagree with UKIP but I would never say they sprung from the BNP or vice versa - UKIP just has a lot of ex BNP members in it. They're totally different parties, they just occupy similar roles nowadays and UKIP are far more successful. The fact that UKIP now occupies the same role as the BNP i.e. far-right anti-immigrant protest vote and has many ex BNP members is what makes them racist - not the fact that they're in any way related to each other "genealogically" or whatever. The BNP are a spent political force - that's why their now expelled ex leader Nick Griffin is advocating a vote for UKIP, albeit "holding his nose", as he said.
If you were wondering about them being comparable in terms of policy to the BNP or UKIP then you would be a bit more correct, although the BNP are really, really extreme (as in "end immigration now, deport immigrants, build a prison for pedophiles on the South Sandwich islands" etc) - far more so than SnG ever were. SnG were just guys that liked to wear kilts, rally at the Bannockburn battle site with the bagpipes playing and complain about English people. They're closer to UKIP, but with the intellectual and political nuance/strategy of the National Front. I'd say they're actually closest to the National Front of all in terms of their activities but NF were pretty terrible. I don't think SnG ever committed attacks like they did. If I had an ex SnG member here he'd probably explain to me that to compare them to NF would be an insult of the highest order but I'm just going by outward resemblance.