I have at best a passing interest in the "legitimacy" of the reconciliation process, but James Joyner pretty much dismantles the current liberal talking point that Republicans use reconciliation to pass controversial bills all the time:

Almost every act passed under reconciliation (8/15) has in fact been a budget bill.  And most of those that weren't (5/7) were tax bills.  The two outliers:  The 1996 welfare reform act and the 2007 student aid package.  Why those were passed under reconciliation isn't made clear.

What's also interesting is that the vast majority of these bills were absolute slam dunks.  Most (8/15) were passed by filibuster-proof  supermajorities, meaning that reconciliation wasn't used as an end-around to avoid a cloture vote.

The argument that Republicans were more likely to use the process than Democrats is meaningless, simply reflecting the fact that Republicans have dominated the Senate over the period in question.   Reconciliation was used six times during the Reagan administration but only once on a bill that didn't have supermajority support.  The Republicans controlled the Senate for all but the last of those votes.   The Democrats then used it for two borderline votes.  The Republicans used it for two slam dunks, one vote that didn't quite have a filibuster-proof margin, and one 51-50 vote in which VP Cheney had to break the tie.

The bottom line is that using reconciliation as an end-around to avoid filibusters is exceedingly rare, having happened at most 7 times since 1980.  Of those 7 cases, all were budget or tax measures.  So, using reconciliation to avoid a supermajority on health care reform would simply be unprecedented.