He's a good singer, no doubt.
Painfully New-Jersey sometimes, but a nice bloke from all I've heard about him. Never saw him give anything but the best live either even if the stage raps make you wince sometimes. And unlike many, I did not think he was the nadir of Deep Purple, his performance with DP at Hammersmith on the Slaves & Master tour is a fond memory, he sang great and the band was recharged and very musical. He sang Burn AND Highway Star without making you cringe - something all other Purple singers have failed at (Coverdale, Hughes) or not even attempted (Gillan) - and really shone on the stuff he had co-written on the then current album. Yes, it was AOR-ish, but good AOR-ish and not "Deep Rainbow" either as DP had a groove - courtesy of swinging Ian Paice and Jon Lord, the Keith Richards of Hammond Organ - that eluded
any Rainbow line-up which all sounded stiff and teutonic to me.
His less than convincing stage-presence and the fact that his voice is too variable for his own good have kept him from climbing to higher stardom I think.
And with the fact that he lost all his hair as a child now in the public domain for some years, it's really time to get a different wig - a shorter one - if he must insist on wearing one. I think he would look cooler as a frontman nowadays just in his bald natural state. He's looking silly for a sixty-year old now.
That said, if you are not an AOR hater, then there is no way denying the man's talent in that particular area of music.
http://www.youtube.com/watch?v=d0HTglse8Zo&feature=results_main&playnext=1&list=PLDC2EE98D5220A123