I've a Beretta Model 21, which I believe evolved into the current "Bobcat" over the years. I'd not consider it reliable enough for carry, but it certainly is reliable enough for a fun plinker, although misfires can be rather common with some brands of ammo.
I've no experience with the TPH, priced too high for my tastes.
IMHO, no small .22LR will be really reliable -- its said that's why JMB invented the .25ACP after he couldn't make .22LR reliable in such small guns.
For a small .22lr plinker I really like my Walther P22, or my FEG SMC-22 (a PPK sized .22LR). P22 being polymer is lighter.
--wally.