For consistency (and inherent laziness) I prefer the PEQ for boosting and a whole slew of pickup tone enhancements. While amp block, GEQ, etc. are useful and quick and easy - so is the PEQ if its just a simple boost: But: when the tone needs more finesse*: it's ready to go for exacting control over not just the gain, but the center frequency and Q (bandwidth). Plus, since there are up to 5 bands, it allows you to both high and low pass the boost as needed; to basically sculpt the boost to do whatever you please: to fatten up a bridge single coil for the solo, to add bite to specific upper mid frequencies with a humbucker, or to cut mid thickness out of the neck pickup for an alternative rhythm tone, and so on. With a particularly resonant semi-hollow guitar or with P90s (as examples), you can add in a narrow band of attenuation to keep inherent resonances in check. Yes, there is a learning curve to parametric equalizers: but so worth while for precise tailoring of guitar to amp, when you need to go beyond basic amp gain and tone controls.
In a similar vein, the Drive Block EQ adjustments have extended flexibility over their hardware incarnations when you want a dirt pedal to do the dirty work: Changing the range of the EQ, in say a Tube Screamer or whatever, can be set to have a bit more or less bass to better hit the amp the way you want.
*Eg: This can be useful in some high gain situations in reducing high end hash or fizz - by means of amp distortion harmonics being generated from a more precisely targeted range of the pickup signal than what the guitar volume and tone controls allow.
