hspice vs. pspice
From my experience and from what i've read in a book PSpice is more user friendly at least when drawing the schematic but when it comes to simulation (read in a book) HSpice is better because it allows to select more integration algoritms and customise them and uses (a dirty trick if you ask me) a method (one of many) of reaching convergence wich consists of raizing the conductance (1/ohm, lowering ohm) that is connected with each device in the circuit (i hope i understood it right), and a really good advantage of HSpice over PSpice is the much better device models wich lead to less problems with convergence and a more accurate simulation.
In general i would say that HSpice is a lot better than PSpice but is a lot more difficult to master.
this is my personal opinions and i don't know much about it (i only know the things i've read, the experience i've aquiered, and the problems i've encountered and it is not much, other people know A LOT MORE than i do because i'm just starting now)