I have purchased a Lowrance HDS-5m Gen 2 that I want to use with Reefmaster. What transducer/sounder do i need to purchase? Do I need to have a Structure Scan or will a standard transducer work?

For mapping only 2D transducer is need (200kHz), but if you want in futur to do side mocaic you will need structure scan that you can buy later.

Just a notice, the "m" models of the HDS-series does not support Echo sounder funtion, should not even have a connector for it.. :(

As Ankfoot said, the m-models does not include a sounder and can not be used on it's own for collecting the depthdata you need. In order to use HDS m-models you need to have one (or more) of the following connected to it through ethernet.
- BSM-1 sounder module
- SonarHub sounder module
- BSM-2 or BSM-3 sounder module(s)
- Any HDS model that has buildt in sonar, such as the HDS x-models or a regular HDS.

Thanks to everyone for your help. I am returning the HDS-5m and am getting the HDS-5X Gen2 in its place. This unit will work with the standard 83/200 KHz transducer wont it? I will only be mapping freshwater bodies of water. Will i need anything else or will this do?

I am pretty sure the 'X' is a sounder only - it has no GPS or mapping facilities. To create maps you need to be able to combine depth and position, ideally on one unit (it is possible to combine output from several, either via ethernet or NMEA0183 but it is easier if you can do it on one machine).
To do this with something from the HDS series you need a model without the 'm' or 'x' suffix, which has both GPS and sonar and can also be used to display your finished maps.

What would be a good unit to consider?

Would the HDS-7 Gen2 Insight work?

What you need is a standard HDS. Ie no "X" or "M" in the name.

HDS 5x - sonar only
HDS 5m - chartplotter only
HDS 5 - both sonar and chartplotter.

So yes, HDS 7 will work. :)

As for your question of what transeducer to use, you should tell us a bit more. For shallow water the HST-WSBL will be fine, but there is a wide range of ducers available depending on your usage. For mapping purposes only, a ducer with a narrow beam in 200 kHz is the best choice, like Airmar P66 (transom mount), B60 (through hull). For deep water a TM260 might be a better choice etc. But if you intend to look for fish as well, a wider coneangle might be a better choice, once again depending on what depths you normally venture into.

I will be in fresh water only to depths of less than 100'. Below are the features included with the bundle for the HDS-7 Insight. Hopefully it will have everything i need.

000-10869-001 Features:

•Fishfinder/Chartplotter with LSS-2 Bundle
•Includes LSS-2 StructureScan HD Sonar
•Insight™ USA Coverage Combines Lake & Nautic Maps
•Built-in Enhanced U.S. Base Map
•New SolarMax Plus 6.4" Display
- High Brightness 480x640 pixels Display
- Sunlight Viewable Screen/Keypad LED Backlighting
•High Definition Fishfinding
- Superior Clarity
- Phenomenal Separation Of Fish Targets
- Improved Underwater Fish-Holding Structure
- Exceptional Fish Finding Performance
- Peerless Bottom Tracking Performance
- Enhanced Responsiveness
- Faster Start-Up
- Fast Chart Panning & Zooming Speeds
- COLORLINE™ Enhances Target Separation
•Built-In Broadband Sounder
•2x Processor Speed
•Faster Start-up & Menu Operation
•Lightning-Fast Chart Panning & Zooming Speeds
•Built-in Recording Capability
•Enhanced Menu Structure Offers Quick & Easy Access
•Supports all Navionics® Content
•Supports Legacy Lowrance Charts
•SD/MMC Memory Card Slot
•SIRIUS Satellite Weather & Stereo-Quality Radio Capability
•Intuitive & Ergonomic Keyboard Design
•Plug-&-Play Operation
•TrackBack™ Functionality
•Simplified High Speed Ethernet Based Networking
•Internal 16-channel GPS+WAAS Antenna
•Lightning-fast Redraws & Display Refresh
•NMEA 0183 Compatible
•NMEA 2000® Network Connectivity
•Maximize Fuel Economy w/ Fuel Flow Sensors
•Precision Temperature Sensor
•83/200 kHz Transducer Included

Trust me, I'm quite familiar with the HDS-series. ;) (I'm ProStaff for the Norwegian agent for Lowrance, and have three HDS units in my own boat.) As I said, any HDS without the X or m in the model name will do the trick.

The OEM Lowrance ducer called HST-WSBL will do everything you need it to do in those depths.

As with all sonar, take care when mounting it in your boat. Take special care with placing the ducer in the best possible place, and try to avoid running the cable going from the HDS to your ducer alongside other electrical cables.

Thank you all very much for the information. I am sure i will have more questions when i get ready to create the maps. Have a great weekend everyone!