Go for it, it's a no brainer for what it costs. I'm listening to them right now, and I've had Blon 03 since it came out, and can definetely say that it remains the main characteristics of BL-03's sound signature but with a faster and tighter bass response. Upper midrange and treble feels a bit improved (in a positive more cohesive way) and i found the overall sound better and more balanced and mature than BL-03, but as with BL-03, you'll have to experiment and try with different sets of tips to get the most of them. Spinfit CP-100's and CP-145's along with inverted KZ starlines are the ones for me that sound best. As far as cable goes, I'm running them with a balanced Kbear Ryhme cable.
BL-01 is for sure an upgrade to BL-03 (especially in quality of the bass) . They have retained the warm liquid sound signature, but without the muddy slow bass) . As it's even cheaper than BL-03 , it's a WIN and I expect it's gonna sell better than BL-03 and will probably become the new king of budget chi-fi audio.