I am seeking your advise on Shmups.
Recently I have discovered 'the real deal' (i.e.JAMMA games).
I am looking for real arcade/JAMMA Shmups (hopefully vertical ones).
However, I am a newbie to Shmups.
I have played Parodius on GB/SNES, Super R-Type, Burai Fighter Delux, Super Probotector and maybe some others, but my main focus is on Vs.Fighters like SFZ etc.
The last Shmup I have attempted was Ikaruga on GC...but I have to admit it was beyond my capabilities and understanding (of gameplay etc)

I have been googling for a while (youtube) for demos of Shmups (Raiden, Progear, Guwange, Dodonpatchi, R-Type Leo, Parodius, Darius, Aero Fighers, 19xx etc) to name a few.
So far, the only game that could tickle my fancy was 'Viewpoint' (I alwas wanted to have and play that game)

So my question to you hardcore Shmuppers is:
What Shmup would you consider as an entertaining 'entry' to Shmups in general (pro/cons)?
For example, i find Ikaruga 'fun' until stage 2 on 'easy', but all the technicals are too advanced to me (maybe like Soul Calibur to a Fighter newbe)

Later games have the habit of serving a core community, so they may demand a 'working knowledge' of the past 2-5 year or so (IMHO).
Thank you for your consideration and advice.
-MrSandman