It's difficult to judge popularity solely on numbers sold because of the growth of the Busse buying population since the early years, but I don't think any CG Busse has increased more in value percentage-wise since release or to a higher value over its life span than the original SHBM. There are a few limited-release models like the axe that have increased more because of rarity, but in terms of popularity the original CG SHBM went for around $350 as I recall and a mint version of the standard, unswedged combat version today brings 3X to 4X that. INFI Steel Hearts also perform well, not quite at that level, and Basics certainly have performed well also, but are in the 2X original value range. That's still remarkable considering the large numbers of Basics originally produced, and with many still in circulation.