300 watts loud enough for band?

[Arthur Strand]

You need to equip yourself for the venues as much as the band, e.g. A smallish hall or club
would mean that a combo with 1 x 15" speaker would suffice.
As you measure up each venue then you know what your back-line requires until you arrive at gargantuan festival sites when everything goes through the sound system and you use whatever suits you best.
To turn up the volume to be twice as loud means 10 times the wattage. A 200 watt amp is only twice as loud as a 20watt one.

 

[Jack]

$700 to work with?

Used GK Backline 600 and an Avatar 410. Done. This will blow the face off that Marshall POS and outlast it by a lifetime. Expandable if you need more, salable if you change your mind. Not to mention lighter.

This. I know you like the Marshall, but that amp probably isn't enough. And even if it is, you can do a lot better for your money. Put that coupon to some other use.