I think the title is revealing. I'm planning to use 2 multi-meters to get a better perspective of my circuits. Is there any drawback in this situation i should be aware?
Yes, that works. However, keep in mind that no meter is perfect. Ideally, voltmeters have infinite impedance and current meters 0 impedance. Real ones don't, of course.
To the extent the meters aren't perfect, particulary the current meter, it will affect the system while trying to measure it. The current meter will cause some voltage drop proportional to the current. You have to be aware of this and possibly account for it. For example, if the voltage drop across the current meter is too big to just ignore, you have to consider carefully on what side of the current meter you measure the voltage, and whether your system can tolerate the voltage drop in the first place.
Yes, you can. No real draw back unless you get to very small fractions of a volt or micro amp ranges and your precision requirements are tight. Or very high voltages and currents that your multimeter wasn't designed to handle well.
Bear in mind we're assuming digital voltmeters here, an analog meter will have an ohms per volt characteristic (google is your friend if you don't understand this).
Digital meters usually have a fixed impedance but this value will dependly largely on the quality (and price) of the meter.
I agree about probe fuse resistances being high, stick the meter onto ohms and short the probes, on mine it's about 8 ohms.
I don't think it is a big deal, you can use. But calibration matters before you taking the reading. Do it couple of times. So you can stick to the precise value