Originally Posted by
rydabent
Derailers are just like most products, you get all the quality and performance when you reach mid level. Ones above mid level pretty much get into glitz and snobbery.
True, but what is that threshold level? For some, that level is Deore for mountain derailleurs, 105 for roadies. I used Acera front and STX rear derailleurs on my old hybrid and it seemed to work very well, after an initial break in period and subsequent fine adjustment by my LBS. Now I have Sora front and Tiagra rear on my current ride, along with Tiagra shifters and it seems to work very well, in fact better now that I have figured out how to correctly use my triple chainring.
My view is, upgrading derailleurs may not fix the problem or issue OP is experiencing. Altus FD/Alivio RD should be adequate for the level of OP's bike, though if he wants to upgrade to Deore or higher to get smoother shifting and somewhat lighter components (though trivial compared to the weight of his bike), it is his money.