Gday mate nice part of the world for sure
for that budget you really could have quite easily your cake and eat it too with some biscuits left in the tin for after dinner coffee.
the 588 is a solid performer for sure. it does not have long legs on it features wise but they are pretty solid units "untill the screens delaminate" we often down here pair 588s with 175hws which gives the unit a wide beam 200khz 1kw option "but obviously neglets any lower frequrency 50khz option. "
this is often why we have seen the rise in populatory of more ocmplete MFD solutions from all the big brands "furuno included"
id say though that wanting something easy to use is first on the priority list below "within budget... obviously" it really doesnt matter how good the system can deliver decent returns if you cant operate it to that level or find it frustraitng to under stand it
alot of cause of sonars performance comes from the transducer itself "and its placement on the boat" its worth asking the question of "what sort of boat do you want to install this on" about now.
id say this is a good idea opener though and a there are a lto of cominations
My recomendations would be
Garmin 8410xsv with a SS175H as a starter
-Reasons
the 588 furuno you have been looking at is a vertial 8" system low resolution sounder only system . this is catered for comfortably with the 10" high resolution system in the 8410
the 1022xsv is actually obsoleted unit "in some ways" system but still offers physical key only control over a 10" system whilst over the furuno offering "CHIRP" frequencies and fixed tone pulse frequencies. and gps etc.
The 8410 Is a full HD screen, offering a fair amoutn more resolution over those other systems equating to it being easier to read the defitiion of targets "especially closer together"
Can run dual 1kw chirp signals "with the right transducer configueration you can actually run 3x 1kw chirp frequecies should you want to"
stupidly easy to use (not a sales pitch, there are some very very cool features that allow for you to safe presets of perticular sonar settings so when you change fishinfg grounds you can at one press of a button have your sonar set up for those areas "shallow.. deep... bottom coverage.... night time . how ever you like "
Budget wise. it would leave a few thousand left in the kitty other things and or towards installtion.
If you are keen on physical keys you could add a GRID physical remote control (say a grid 20 to connect to your existing NMEA2K network) or GRID10 for ethrenet intergration. or a wireless GPSMAP remote control. this will give you all the characteristics of a physical control as well as the benifits of touch screen "Which do come in handy for mapping in perticular"
speaking of mapping
It also gives you access to garmins pretty dam good collection of maps "including their new high resolution relief shading maps"
i realise this is a lot to get through so feel free to shoot through any questions
Moose