if its the snap-on stuff then
the software code is easily explained,
eg 10.2 10.4 10.6 etc
the 1st part is the year its introduced, i.e 2010
9.2 is 2009 8.2 is 2008 11.2 is 2011 etc
the second part comes up in .2 intervals and its just the number of update for the year, he bigger the number the later the update
eg 10.4 is newer that 10.2 etc
they generaly cover up to that year eg 10.2 will cover upto 2010 cars etc
but more recently the newer updates are also adding more manufacturers as well
the latest 12.4(i think) had added jaguar, so if you wanted to do a 2008 jag then you'd need to get the latest software,
the solus itself is a very capable machine, but again it becomes more useful with newer software as the more up to date software lets you do dpf regeneration, but the older software doesn't have this facility,
if you do a lot of jap stuff then the launch is without a doubt better but the snap on software is catching up recently, but if is mainly european stuff you do then the snap-on stuff is better,
overall they are both good capable machines, they both have strenghts and weaknesses
it depends on what you want to do with it, both will let you down at some point where the other would have succeded, but unless you want to buy both theres no getting round that
if you do go for the solus, then i highly recommend getting the 1 with the latest software you can afford