Yes, there are some differencess...
...But not with regards to their chances of success. The MPL had no chance whatsoever of succeeding; there were several flaws in its design which were 100% guaranteed to fail (the issue with the landing gear deployment causing premature thruster termination was at LEAST as serious as the heat shield issue that Gary has been raising, for example). The primary difference between Beagle II & MPL is that one incurred a small amount of private debt, while the other was financed on the on the margins of a large amount of public debt.